If you own one of those devices not listed in the M1 certified list of 5G SA devices, the good news is that, we receive news from our affiliate that they were able to enable 5G SA on the POCO M4 Pro 5G running in 5G SA with VoNR. The trick is to enable the hidden SA option (Watch youtube video below to see how you can enable the hidden option).
It is also noted that previous models like the Samsung A42 5G also seem to work. It looks like the 5G SA lock was removed at the telco end.
The screen shot is captured by running Speedtest on the POCO M4 Pro 5G. VoNR also works.
Unfortunately, iPhone 12 users are left out. Samsung users with S20 devices will not work with 5G SA.